The present invention relates to a card operated lock in which a so-called mechanical card lock of the type using a punched card as a proper key incorporates there in a so-called pin tumbler.
Even though there has been a strong demand to easily change a cylinder lock of a room at any suitable time in order to prevent a mala fide person from unlocking or opening the lock of the room by using a duplicated key and stealing articles from that room in hotels or the like where various guests stay, it has been considerably difficult to do so because it takes a long period of time and is cumbersome to replace an old cylinder with a new one in the case of a mechanical cylinder lock.
In order to overcome such problem, there have been devised and demonstrated electrical locks of the type which can be unlocked or opened when magnetic cards or punched cards are used as proper keys. However, such electrical locks comprise a power supply, a card reader, a control unit and an electronic lock so that they are very complicated in construction and consequently are very expensive. Furthermore, considerably high costs and much labor are required to install such electrical locks and accomplish associated wiring operations.
In view of the above, a novel mechanical locking device of the type using a punched card as a proper key is disclosed in detail in Japanese Patent Application No. 6805/1982 (Japanese Patent Application Laid-Open No. 123980/1983), whereby the above-described problems are satisfactorily overcome to some extent.